砂土边坡地震动力响应离心模型试验

为研究砂土边坡的地震响应规律,采用El Centro波作为地震输入,在50倍重力加速度条件下进行边坡的动力离心模型试验。试验在土工离心机及专用振动台上实施,利用加速度传感器记录模型不同位置地震响应的加速度时程并进行频谱分析。结果表明:最大响应发生于坡顶,该处地震波反应谱放大系数最大值为4.78。地震波反应谱不同频率成分放大效果不同,与5.7~6.7 Hz的频率成分相应的反应谱放大最大。边坡自下而上存在地震响应放大现象,边坡上部响应大于底部,靠近边坡斜面的响应大于内部。

Centrifuge model test of the seismic response behavior of a sand slope

A centrifuge model test of a sand slope subjected to an El Centro earthquake was carried out on a centrifuge shaking table at 50 gravitational accelerations to investigate the seismic response behavior of sand slopes.Acceleration time histories were recorded by accelerometers at different locations on the model to calculate the response spectra.The maximum response occurred at the crest where the peak spectrum amplification factor was 4.78.Different constituent frequencies of the input motion spectrum were amplified to different degrees.The constituent frequency with the maximum amplification factor was 5.7-6.7 Hz.The slope response was amplified as the seismic motion propagated upwards through the slope.The response of the upper layer was greater than that of the lower layer while the response of the zone adjacent to the inclined surface was greater than that of the internal slope.